23 (c) George investigates a metal filament bulb. George tries to explain how the resistance changes when the bulb is switched on. He uses the model below.
Current in a conductor is the flow of charge carriers called protons. The charge carriers collide with the atoms (ions) in the conductor. This makes the atoms vibrate less which •
causes an increase in collisions, decreasing the resistance
•
increases the temperature of the conductor.
George has made three mistakes in his model. State the three mistakes he has made and write down the corrections. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... .............................................................................................................................................. [2] [Total: 6]
Question 14 begins on page 24
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